“Twice as many A as B” means A = 2B.

It’s the same as saying it in these alternative ways:

“A is twice as many/much as B.”

“Twice as many/much A as B.”

“Two times as many/much of A as B.”

“B is half as many/much as A.”

“Half as many/much B as A.”

“As many” means the same number.

Twice as many means two times as many.

Twice as many A as B：means that more for A than for B

Sample question:

There were 6036 people at a book fair. There were 3 times as many men as women at the fair. How many more men than women were there?